The present invention relates to an open-ended wrench having a ratcheting action to permit application of the wrench in confined spacements.
Open-ended wrenches are often required for application to a nut or bolt head in a confined environment. Thus the open-ended wrench can be extended inwardly through a relatively small opening in alignment with the nut or bolt head for tightening or loosening of the corresponding elements. In location with a turning space of about 30 degrees, the open-ended wrench may be advantageously applied by merely reversing of the wrench position with each turn. In such systems, of course, the wrench must be inserted, turned, removed, reinserted and so forth. The action is rather time consuming and may be rather difficult if the element is not turned precisely the proper amount.
Closed end type wrenches have been developed into socket form with a ratcheting attachment provided. This permits the application of the unit directly to the element and, with a convenient reciprocating rotation of the operating handle, the nut or bolt is turned. Although various other ratcheting wrenches have also been suggested they generally operate on the basic principle of a pipe wrench more than an open-ended wrench. For example, U.S. Pat. No. 1,635,930 discloses a wrench having a pivoted pawl or jaw and a fixed jaw defining an offset wrench opening. The jaws are angularly offset to the wrench arm and provided with serrated faces generally in the nature of the usual pipe wrench, vice-grip or the like. More recently, U.S. Pat. No. 2,655,064 which issued Oct. 13, 1953, discloses a ratcheting open-jawed wrench having an encircling moveable jaw with a bill-like portion which is adapted to wrap about the end of an arm of a wrench member to define a ratcheting wrench. The bill-like portion is formed with a plurality of offset portions to permit engagement with a hex-shaped nut, bolt head or the like. The offset bill-like construction requires that the unit be inserted more or less to the side of the head rather than directly thereto as with a conventional open-ended wrench. A somewhat similar device is shown in the early U.S. Pat. No. 1,072,090 which issued Sept. 12, 1913 and in which an angularly offset opening includes a multiple face fixed jaw and multiple face moveable jaw provided for similar functioning and operation. Although such prior art devices have been suggested, they do not function to duplicate the function of an open-ended wrench and generally will not provide the various features of an open-ended wrench. Thus, the prior art does not allow the direct in-line mounting and insertion, nor does it provide for the convenient reverse positioning of the tool for turning within a limited environment. In addition the prior art essentially uses the principle of a pawl attached to a torque converting jaw by a pin connection, with the stress applied to the pin member during the application of the closing or loading of the unit to rotate the work. The forces are generally transmitted from the fixed jaw to the pivot element and therethrough to the moveable jaw.
The prior art can therefore be appropriately characterized as having various characteristics of a pipe wrench, namely, the offset handle and opening the serrated gripping surface for gripping of a member, force transmission through the work and a connecting pin, or the like.